Changes

  | part    = Critical elements of the petroleum system

  | part    = Critical elements of the petroleum system

  | chapter = Sedimentary basin analysis

  | chapter = Sedimentary basin analysis

  | frompg  = 4-1

  | frompg  = 4-86

  | topg    = 4-123

  | topg    = 4-91

  | author  = John M. Armentrout

  | author  = John M. Armentrout

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch04/ch04.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch04/ch04.htm

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

Four reservoir intervals are productive in the East Breaks 160-161 minibasin: ''Glob alt, Glob M, Hyal B'', and ''Trim A'' horizons. Reservoir intervals are named for the regionally useful bioevent species stratigraphically above the reservoir. These bioevents most often occur within condensed sections. All four reservoir intervals are interpreted to be gravity-flow sand deposits.<ref name=ch04r7>Armentrout, J. M., 1991, Paleontological constraints on depositional [[modeling]]: examples of integration of biostratigraphy and seismic stratigraphy, Pliocene–Pleistocene, Gulf of Mexico, in Weimer, P., Link, M., H., eds., Seismic Facies and Sedimentary Processes of Submarine Fans and Turbidite Systems: New York, Springer-Verlag, p. 137–170.</ref> Only the ''Glob alt'' reservoir is considered here.

Four reservoir intervals are productive in the East Breaks 160-161 [[minibasin]]: ''Glob alt, Glob M, Hyal B'', and ''Trim A'' horizons. Reservoir intervals are named for the regionally useful bioevent species stratigraphically above the reservoir. These bioevents most often occur within condensed sections. All four reservoir intervals are interpreted to be [[gravity]]-flow sand deposits.<ref name=ch04r7>Armentrout, J. M., 1991, Paleontological constraints on depositional [[modeling]]: examples of integration of biostratigraphy and seismic stratigraphy, Pliocene–Pleistocene, Gulf of Mexico, in Weimer, P., Link, M., H., eds., Seismic Facies and Sedimentary Processes of Submarine Fans and Turbidite Systems: New York, Springer-Verlag, p. 137–170.</ref> Only the ''Glob alt'' reservoir is considered here.

==''Glob alt'' sequence deposition==

==''Glob alt'' sequence deposition==

==''Glob alt'' isochron and seismic facies map==

==''Glob alt'' isochron and seismic facies map==

''Glob alt'' sandstones of the East Breaks 160-161 field occur within an [[isochron]] thick where hummocky seismic facies downlap toward and are buried by parallel low-amplitude seismic facies indicative of hemipelagic mudstone drape.<ref name=ch04r7 /> [[:file:sedimentary-basin-analysis_fig4-46.png|Figure 1]] shows an isochron and seismic facies map of the ''Glob alt'' reservoir interval. The internal reflections of the mounded facies (1) downlap away from the isochron thick and toward the parallel seismic facies (2). Neither the isochron nor the seismic facies is mapped north of the fault due to poor data quality.

''Glob alt'' sandstones of the East Breaks 160-161 field occur within an [[isochron]] thick where hummocky seismic facies downlap toward and are buried by parallel low-amplitude seismic facies indicative of hemipelagic [[mudstone]] drape.<ref name=ch04r7 /> [[:file:sedimentary-basin-analysis_fig4-46.png|Figure 1]] shows an isochron and seismic [[facies map]] of the ''Glob alt'' reservoir interval. The internal reflections of the mounded facies (1) downlap away from the isochron thick and toward the parallel seismic facies (2). Neither the isochron nor the seismic facies is mapped north of the fault due to poor data quality.

==Seismic profile==

==Seismic profile==

<gallery mode=packed heights=300px widths=300px>

<gallery mode=packed heights=300px widths=300px>

sedimentary-basin-analysis_fig4-50.png|{{figure number|8}}block diagram of the depositional model for the Glob alt reservoir interval. From Armentrout et al.<ref name=ArmentroutEtAl_1991 />. Courtesy Springer-Verlag.

sedimentary-basin-analysis_fig4-50.png|{{figure number|8}}block diagram of the depositional model for the Glob alt reservoir interval. From Armentrout et al.<ref name=ArmentroutEtAl_1991 />. Courtesy Springer-Verlag.

sedimentary-basin-analysis_fig4-39.png|{{figure number|9}}Depositional facies map for the Glob alt interval’s basal sequence boundary, constructed by integrating the biofacies map, the net sandstone map, and the seismic facies map. After Armentrout (1991); courtesy Springer-Verlag.

sedimentary-basin-analysis_fig4-39.png|{{figure number|9}}Depositional facies map for the Glob alt interval’s basal sequence boundary, constructed by integrating the biofacies map, the net sandstone map, and the seismic facies map. After Armentrout;<ref name=ch04r7 /> courtesy Springer-Verlag.

</gallery>

</gallery>

==Accommodation space==

==Accommodation space==

[[file:sedimentary-basin-analysis_fig4-31.png|300px|thumb|{{figure number|10}}Composite chronostratigraphic chart that serves as an age model for the GOM basin Pliocene and Pleistocene, summarizing nine studies published between 1982 and 1993. From Armentrout (1996); courtesy The Geological Society, London.]]

[[file:sedimentary-basin-analysis_fig4-31.png|300px|thumb|{{figure number|10}}Composite chronostratigraphic chart that serves as an age model for the GOM basin Pliocene and Pleistocene, summarizing nine studies published between 1982 and 1993. From Armentrout;<ref name=ch04r9 /> courtesy The Geological Society, London.]]

Differential loading of the mobile salt resulted in some syndepositional subsidence and accommodation of the ''Glob alt'' sand-prone [[isochron]] thick. The apparent thickening into the north-bounding [[growth fault]] is due to the maximum differential subsidence and isochron thickening being coincident with the fault trace of a much younger growth fault phase. Biostratigraphic calibration of the fault system indicates most, if not all, of the fault offset occurred during middle Pleistocene time, after the ''Trifarina rutila bioevent'' (= ''Ang B'') dated at 1.30 Ma ([[:file:sedimentary-basin-analysis_fig4-31.png|Figure 10]]). This is more than [[length::1.5 m]].y. after deposition of the ''Glob alt'' sands.

Differential loading of the mobile salt resulted in some syndepositional subsidence and accommodation of the ''Glob alt'' sand-prone [[isochron]] thick. The apparent thickening into the north-bounding [[growth fault]] is due to the maximum differential subsidence and isochron thickening being coincident with the fault trace of a much younger growth fault phase. Biostratigraphic calibration of the fault system indicates most, if not all, of the fault offset occurred during middle Pleistocene time, after the ''Trifarina rutila bioevent'' (= ''Ang B'') dated at 1.30 Ma ([[:file:sedimentary-basin-analysis_fig4-31.png|Figure 10]]). This is more than [[length::1.5 m]].y. after deposition of the ''Glob alt'' sands.

[[Category:Sedimentary basin analysis]]

[[Category:Sedimentary basin analysis]]

[[Category:East Breaks]]

[[Category:East Breaks]]